Bernard Madoff remains haunted by the suicide of his oldest son, he said in his latest interview from prison.

The fraudster, who is serving a 150 year sentence for running a $65 billion Ponzi scheme, told CNN Money, "I'm usually up at 4:30 in the morning because I can't sleep."

"I was responsible for my son Mark's death and that's very, very difficult," he said during the phone interview. "I live with that. I live with the remorse, the pain I caused everybody, certainly my family, and the victims."

Madoff's son killed himself in 2010, on the two-year anniversary of his father's arrest.

Madoff said he began ripping investors off in 1987, shortly after the stock-market crash. But he said he hoped the fraud would be short-lived.

"It was certainly never my intention for this to happen," Madoff said. "I thought I could work myself out of a temporary situation but it kept getting worse and worse and I didn't have the courage to admit what I had done. It created a major problem."

Still, life isn't all bad for Madoff: After four years in prison, he's received something of a promotion, from commissary clerk to "taking care of the telephone and computer systems." It doesn't involve any technical skill to "make sure they're working and they're kept clean," but it also only takes "a few hours" each day.

It also doesn't pay much: The former billionaire earns $40 a month—and had no money left in his prison phone account, requiring him to call CNN collect.

Editor's Note

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